1 /* -*- mode: c; c-basic-offset: 8; -*-
2  * vim: noexpandtab sw=8 ts=8 sts=0:
3  *
4  * suballoc.h
5  *
6  * Defines sub allocator api
7  *
8  * Copyright (C) 2003, 2004 Oracle.  All rights reserved.
9  *
10  * This program is free software; you can redistribute it and/or
11  * modify it under the terms of the GNU General Public
12  * License as published by the Free Software Foundation; either
13  * version 2 of the License, or (at your option) any later version.
14  *
15  * This program is distributed in the hope that it will be useful,
16  * but WITHOUT ANY WARRANTY; without even the implied warranty of
17  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
18  * General Public License for more details.
19  *
20  * You should have received a copy of the GNU General Public
21  * License along with this program; if not, write to the
22  * Free Software Foundation, Inc., 59 Temple Place - Suite 330,
23  * Boston, MA 021110-1307, USA.
24  */
25 
26 #ifndef _CHAINALLOC_H_
27 #define _CHAINALLOC_H_
28 
29 struct ocfs2_suballoc_result;
30 typedef int (group_search_t)(struct inode *,
31 			     struct buffer_head *,
32 			     u32,			/* bits_wanted */
33 			     u32,			/* min_bits */
34 			     u64,			/* max_block */
35 			     struct ocfs2_suballoc_result *);
36 							/* found bits */
37 
38 struct ocfs2_alloc_context {
39 	struct inode *ac_inode;    /* which bitmap are we allocating from? */
40 	struct buffer_head *ac_bh; /* file entry bh */
41 	u32    ac_alloc_slot;   /* which slot are we allocating from? */
42 	u32    ac_bits_wanted;
43 	u32    ac_bits_given;
44 #define OCFS2_AC_USE_LOCAL 1
45 #define OCFS2_AC_USE_MAIN  2
46 #define OCFS2_AC_USE_INODE 3
47 #define OCFS2_AC_USE_META  4
48 	u32    ac_which;
49 
50 	/* these are used by the chain search */
51 	u16    ac_chain;
52 	int    ac_disable_chain_relink;
53 	group_search_t *ac_group_search;
54 
55 	u64    ac_last_group;
56 	u64    ac_max_block;  /* Highest block number to allocate. 0 is
57 				 is the same as ~0 - unlimited */
58 
59 	int    ac_find_loc_only;  /* hack for reflink operation ordering */
60 	struct ocfs2_suballoc_result *ac_find_loc_priv; /* */
61 
62 	struct ocfs2_alloc_reservation	*ac_resv;
63 };
64 
65 void ocfs2_init_steal_slots(struct ocfs2_super *osb);
66 void ocfs2_free_alloc_context(struct ocfs2_alloc_context *ac);
ocfs2_alloc_context_bits_left(struct ocfs2_alloc_context * ac)67 static inline int ocfs2_alloc_context_bits_left(struct ocfs2_alloc_context *ac)
68 {
69 	return ac->ac_bits_wanted - ac->ac_bits_given;
70 }
71 
72 /*
73  * Please note that the caller must make sure that root_el is the root
74  * of extent tree. So for an inode, it should be &fe->id2.i_list. Otherwise
75  * the result may be wrong.
76  */
77 int ocfs2_reserve_new_metadata(struct ocfs2_super *osb,
78 			       struct ocfs2_extent_list *root_el,
79 			       struct ocfs2_alloc_context **ac);
80 int ocfs2_reserve_new_metadata_blocks(struct ocfs2_super *osb,
81 				      int blocks,
82 				      struct ocfs2_alloc_context **ac);
83 int ocfs2_reserve_new_inode(struct ocfs2_super *osb,
84 			    struct ocfs2_alloc_context **ac);
85 int ocfs2_reserve_clusters(struct ocfs2_super *osb,
86 			   u32 bits_wanted,
87 			   struct ocfs2_alloc_context **ac);
88 
89 int ocfs2_claim_metadata(handle_t *handle,
90 			 struct ocfs2_alloc_context *ac,
91 			 u32 bits_wanted,
92 			 u64 *suballoc_loc,
93 			 u16 *suballoc_bit_start,
94 			 u32 *num_bits,
95 			 u64 *blkno_start);
96 int ocfs2_claim_new_inode(handle_t *handle,
97 			  struct inode *dir,
98 			  struct buffer_head *parent_fe_bh,
99 			  struct ocfs2_alloc_context *ac,
100 			  u64 *suballoc_loc,
101 			  u16 *suballoc_bit,
102 			  u64 *fe_blkno);
103 int ocfs2_claim_clusters(handle_t *handle,
104 			 struct ocfs2_alloc_context *ac,
105 			 u32 min_clusters,
106 			 u32 *cluster_start,
107 			 u32 *num_clusters);
108 /*
109  * Use this variant of ocfs2_claim_clusters to specify a maxiumum
110  * number of clusters smaller than the allocation reserved.
111  */
112 int __ocfs2_claim_clusters(handle_t *handle,
113 			   struct ocfs2_alloc_context *ac,
114 			   u32 min_clusters,
115 			   u32 max_clusters,
116 			   u32 *cluster_start,
117 			   u32 *num_clusters);
118 
119 int ocfs2_free_suballoc_bits(handle_t *handle,
120 			     struct inode *alloc_inode,
121 			     struct buffer_head *alloc_bh,
122 			     unsigned int start_bit,
123 			     u64 bg_blkno,
124 			     unsigned int count);
125 int ocfs2_free_dinode(handle_t *handle,
126 		      struct inode *inode_alloc_inode,
127 		      struct buffer_head *inode_alloc_bh,
128 		      struct ocfs2_dinode *di);
129 int ocfs2_free_clusters(handle_t *handle,
130 			struct inode *bitmap_inode,
131 			struct buffer_head *bitmap_bh,
132 			u64 start_blk,
133 			unsigned int num_clusters);
134 int ocfs2_release_clusters(handle_t *handle,
135 			   struct inode *bitmap_inode,
136 			   struct buffer_head *bitmap_bh,
137 			   u64 start_blk,
138 			   unsigned int num_clusters);
139 
ocfs2_which_suballoc_group(u64 block,unsigned int bit)140 static inline u64 ocfs2_which_suballoc_group(u64 block, unsigned int bit)
141 {
142 	u64 group = block - (u64) bit;
143 
144 	return group;
145 }
146 
ocfs2_cluster_from_desc(struct ocfs2_super * osb,u64 bg_blkno)147 static inline u32 ocfs2_cluster_from_desc(struct ocfs2_super *osb,
148 					  u64 bg_blkno)
149 {
150 	/* This should work for all block group descriptors as only
151 	 * the 1st group descriptor of the cluster bitmap is
152 	 * different. */
153 
154 	if (bg_blkno == osb->first_cluster_group_blkno)
155 		return 0;
156 
157 	/* the rest of the block groups are located at the beginning
158 	 * of their 1st cluster, so a direct translation just
159 	 * works. */
160 	return ocfs2_blocks_to_clusters(osb->sb, bg_blkno);
161 }
162 
ocfs2_is_cluster_bitmap(struct inode * inode)163 static inline int ocfs2_is_cluster_bitmap(struct inode *inode)
164 {
165 	struct ocfs2_super *osb = OCFS2_SB(inode->i_sb);
166 	return osb->bitmap_blkno == OCFS2_I(inode)->ip_blkno;
167 }
168 
169 /* This is for local alloc ONLY. Others should use the task-specific
170  * apis above. */
171 int ocfs2_reserve_cluster_bitmap_bits(struct ocfs2_super *osb,
172 				      struct ocfs2_alloc_context *ac);
173 void ocfs2_free_ac_resource(struct ocfs2_alloc_context *ac);
174 
175 /* given a cluster offset, calculate which block group it belongs to
176  * and return that block offset. */
177 u64 ocfs2_which_cluster_group(struct inode *inode, u32 cluster);
178 
179 /*
180  * By default, ocfs2_read_group_descriptor() calls ocfs2_error() when it
181  * finds a problem.  A caller that wants to check a group descriptor
182  * without going readonly should read the block with ocfs2_read_block[s]()
183  * and then checking it with this function.  This is only resize, really.
184  * Everyone else should be using ocfs2_read_group_descriptor().
185  */
186 int ocfs2_check_group_descriptor(struct super_block *sb,
187 				 struct ocfs2_dinode *di,
188 				 struct buffer_head *bh);
189 /*
190  * Read a group descriptor block into *bh.  If *bh is NULL, a bh will be
191  * allocated.  This is a cached read.  The descriptor will be validated with
192  * ocfs2_validate_group_descriptor().
193  */
194 int ocfs2_read_group_descriptor(struct inode *inode, struct ocfs2_dinode *di,
195 				u64 gd_blkno, struct buffer_head **bh);
196 
197 int ocfs2_lock_allocators(struct inode *inode, struct ocfs2_extent_tree *et,
198 			  u32 clusters_to_add, u32 extents_to_split,
199 			  struct ocfs2_alloc_context **data_ac,
200 			  struct ocfs2_alloc_context **meta_ac);
201 
202 int ocfs2_test_inode_bit(struct ocfs2_super *osb, u64 blkno, int *res);
203 
204 
205 
206 /*
207  * The following two interfaces are for ocfs2_create_inode_in_orphan().
208  */
209 int ocfs2_find_new_inode_loc(struct inode *dir,
210 			     struct buffer_head *parent_fe_bh,
211 			     struct ocfs2_alloc_context *ac,
212 			     u64 *fe_blkno);
213 
214 int ocfs2_claim_new_inode_at_loc(handle_t *handle,
215 				 struct inode *dir,
216 				 struct ocfs2_alloc_context *ac,
217 				 u64 *suballoc_loc,
218 				 u16 *suballoc_bit,
219 				 u64 di_blkno);
220 
221 #endif /* _CHAINALLOC_H_ */
222